Source for javax.swing.plaf.basic.BasicArrowButton

   1: /* BasicArrowButton.java --
   2:    Copyright (C) 2004, 2005 Free Software Foundation, Inc.
   3: 
   4: This file is part of GNU Classpath.
   5: 
   6: GNU Classpath is free software; you can redistribute it and/or modify
   7: it under the terms of the GNU General Public License as published by
   8: the Free Software Foundation; either version 2, or (at your option)
   9: any later version.
  10: 
  11: GNU Classpath is distributed in the hope that it will be useful, but
  12: WITHOUT ANY WARRANTY; without even the implied warranty of
  13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14: General Public License for more details.
  15: 
  16: You should have received a copy of the GNU General Public License
  17: along with GNU Classpath; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 USA.
  20: 
  21: Linking this library statically or dynamically with other modules is
  22: making a combined work based on this library.  Thus, the terms and
  23: conditions of the GNU General Public License cover the whole
  24: combination.
  25: 
  26: As a special exception, the copyright holders of this library give you
  27: permission to link this library with independent modules to produce an
  28: executable, regardless of the license terms of these independent
  29: modules, and to copy and distribute the resulting executable under
  30: terms of your choice, provided that you also meet, for each linked
  31: independent module, the terms and conditions of the license of that
  32: module.  An independent module is a module which is not derived from
  33: or based on this library.  If you modify this library, you may extend
  34: this exception to your version of the library, but you are not
  35: obligated to do so.  If you do not wish to do so, delete this
  36: exception statement from your version. */
  37: 
  38: 
  39: package javax.swing.plaf.basic;
  40: 
  41: import java.awt.Color;
  42: import java.awt.Dimension;
  43: import java.awt.Graphics;
  44: import java.awt.Polygon;
  45: import java.awt.Rectangle;
  46: 
  47: import javax.swing.ButtonModel;
  48: import javax.swing.JButton;
  49: import javax.swing.SwingConstants;
  50: 
  51: /**
  52:  * A button that displays an arrow (triangle) that points {@link #NORTH},
  53:  * {@link #SOUTH}, {@link #EAST} or {@link #WEST}.  This button is used by
  54:  * the {@link BasicComboBoxUI} class.
  55:  * 
  56:  * @see BasicComboBoxUI#createArrowButton
  57:  */
  58: public class BasicArrowButton extends JButton implements SwingConstants
  59: {
  60: 
  61:   /** 
  62:    * The direction that the arrow points. 
  63:    * 
  64:    * @see #getDirection()
  65:    */
  66:   protected int direction;
  67: 
  68:   /**
  69:    * The color the arrow is painted in if disabled and the bottom and right
  70:    * edges of the button.
  71:    * This is package-private to avoid an accessor method.
  72:    */
  73:   transient Color shadow = Color.GRAY;
  74: 
  75:   /**
  76:    * The color the arrow is painted in if enabled and the bottom and right
  77:    * edges of the button.
  78:    * This is package-private to avoid an accessor method.
  79:    */
  80:   transient Color darkShadow = new Color(102, 102, 102);
  81: 
  82:   /**
  83:    * The top and left edges of the button.
  84:    * This is package-private to avoid an accessor method.
  85:    */
  86:   transient Color highlight = Color.WHITE;
  87: 
  88:   /**
  89:    * Creates a new <code>BasicArrowButton</code> object.
  90:    *
  91:    * @param direction The direction the arrow points in (one of: 
  92:    * {@link #NORTH}, {@link #SOUTH}, {@link #EAST} and {@link #WEST}).
  93:    */
  94:   public BasicArrowButton(int direction)
  95:   {
  96:     super();
  97:     setDirection(direction);
  98:   }
  99: 
 100:   /**
 101:    * Creates a new BasicArrowButton object with the given colors and
 102:    * direction.
 103:    *
 104:    * @param direction The direction to point in (one of: 
 105:    * {@link #NORTH}, {@link #SOUTH}, {@link #EAST} and {@link #WEST}).
 106:    * @param background The background color.
 107:    * @param shadow The shadow color.
 108:    * @param darkShadow The dark shadow color.
 109:    * @param highlight The highlight color.
 110:    */
 111:   public BasicArrowButton(int direction, Color background, Color shadow,
 112:                           Color darkShadow, Color highlight)
 113:   {
 114:     this(direction);
 115:     setBackground(background);
 116:     this.shadow = shadow;
 117:     this.darkShadow = darkShadow;
 118:     this.highlight = highlight;
 119:     // Mark the button as not closing the popup, we handle this ourselves.
 120:     putClientProperty(BasicLookAndFeel.DONT_CANCEL_POPUP, Boolean.TRUE);
 121:   }
 122: 
 123:   /**
 124:    * Returns whether the focus can traverse to this component.  This method
 125:    * always returns <code>false</code>.
 126:    *
 127:    * @return <code>false</code>.
 128:    */
 129:   public boolean isFocusTraversable()
 130:   {
 131:     return false;
 132:   }
 133: 
 134:   /**
 135:    * Returns the direction of the arrow (one of: {@link #NORTH}, 
 136:    * {@link #SOUTH}, {@link #EAST} and {@link #WEST}).
 137:    *
 138:    * @return The direction of the arrow.
 139:    */
 140:   public int getDirection()
 141:   {
 142:     return direction;
 143:   }
 144: 
 145:   /**
 146:    * Sets the direction of the arrow.
 147:    *
 148:    * @param dir The new direction of the arrow (one of: {@link #NORTH}, 
 149:    *            {@link #SOUTH}, {@link #EAST} and {@link #WEST}).
 150:    */
 151:   public void setDirection(int dir)
 152:   {
 153:     this.direction = dir;
 154:   }
 155: 
 156:   /**
 157:    * Paints the arrow button. The painting is delegated to the
 158:    * paintTriangle method.
 159:    *
 160:    * @param g The Graphics object to paint with.
 161:    */
 162:   public void paint(Graphics g)
 163:   {
 164:     super.paint(g);
 165:     Rectangle bounds = getBounds();
 166:     int size = bounds.height / 4;
 167:     int x = bounds.x + (bounds.width - size) / 2;
 168:     int y = (bounds.height - size) / 4;
 169:     ButtonModel m = getModel();
 170:     if (m.isArmed())
 171:       {
 172:         x++;
 173:         y++;
 174:       }
 175:     paintTriangle(g, x, y, size, direction, isEnabled());
 176:   }
 177: 
 178:   /** The preferred size for the button. */
 179:   private static final Dimension PREFERRED_SIZE = new Dimension(16, 16);
 180: 
 181:   /** The minimum size for the button. */
 182:   private static final Dimension MINIMUM_SIZE = new Dimension(5, 5);
 183: 
 184:   /** The maximum size for the button. */
 185:   private static final Dimension MAXIMUM_SIZE 
 186:     = new Dimension(Integer.MAX_VALUE, Integer.MAX_VALUE);
 187:   
 188:   /**
 189:    * Returns the preferred size of the arrow button.
 190:    *
 191:    * @return The preferred size (always 16 x 16).
 192:    */
 193:   public Dimension getPreferredSize()
 194:   {
 195:     return PREFERRED_SIZE;
 196:   }
 197: 
 198:   /**
 199:    * Returns the minimum size of the arrow button.
 200:    *
 201:    * @return The minimum size (always 5 x 5).
 202:    */
 203:   public Dimension getMinimumSize()
 204:   {
 205:     return MINIMUM_SIZE;
 206:   }
 207: 
 208:   /**
 209:    * Returns the maximum size of the arrow button.
 210:    *
 211:    * @return The maximum size.
 212:    */
 213:   public Dimension getMaximumSize()
 214:   {
 215:     return MAXIMUM_SIZE;
 216:   }
 217: 
 218:   /**
 219:    * Paints a triangle with the given size, location and direction.  It is 
 220:    * difficult to explain the rationale behind the positioning of the triangle
 221:    * relative to the given (x, y) position - by trial and error we seem to 
 222:    * match the behaviour of the reference implementation (which is missing a 
 223:    * specification for this method).
 224:    *
 225:    * @param g  the graphics device.
 226:    * @param x  the x-coordinate for the triangle's location.
 227:    * @param y  the y-coordinate for the triangle's location.
 228:    * @param size  the arrow size (depth).
 229:    * @param direction  the direction of the arrow (one of: {@link #NORTH}, 
 230:    *            {@link #SOUTH}, {@link #EAST} and {@link #WEST}).
 231:    * @param isEnabled  if <code>true</code> the arrow is drawn in the enabled
 232:    *                   state, otherwise it is drawn in the disabled state.
 233:    */
 234:   public void paintTriangle(Graphics g, int x, int y, int size, int direction,
 235:                             boolean isEnabled)
 236:   {
 237:     Color savedColor = g.getColor();
 238:     switch (direction)
 239:       {
 240:       case NORTH:
 241:         paintTriangleNorth(g, x, y, size, isEnabled);
 242:         break;
 243:       case SOUTH:
 244:         paintTriangleSouth(g, x, y, size, isEnabled);
 245:         break;
 246:       case LEFT:
 247:       case WEST:
 248:         paintTriangleWest(g, x, y, size, isEnabled);
 249:         break;
 250:       case RIGHT:
 251:       case EAST:
 252:         paintTriangleEast(g, x, y, size, isEnabled);
 253:         break;
 254:       }
 255:     g.setColor(savedColor);
 256:   }
 257:   
 258:   /**
 259:    * Paints an upward-pointing triangle.  This method is called by the 
 260:    * {@link #paintTriangle(Graphics, int, int, int, int, boolean)} method.
 261:    * 
 262:    * @param g  the graphics device.
 263:    * @param x  the x-coordinate for the anchor point.
 264:    * @param y  the y-coordinate for the anchor point.
 265:    * @param size  the arrow size (depth).
 266:    * @param isEnabled  if <code>true</code> the arrow is drawn in the enabled
 267:    *                   state, otherwise it is drawn in the disabled state.
 268:    */
 269:   private void paintTriangleNorth(Graphics g, int x, int y, int size, 
 270:           boolean isEnabled)
 271:   {
 272:     int tipX = x + (size - 2) / 2;
 273:     int tipY = y;
 274:     int baseX1 = tipX - (size - 1);
 275:     int baseX2 = tipX + (size - 1);
 276:     int baseY = y + (size - 1);
 277:     Polygon triangle = new Polygon();
 278:     triangle.addPoint(tipX, tipY);
 279:     triangle.addPoint(baseX1, baseY);
 280:     triangle.addPoint(baseX2, baseY);
 281:     if (isEnabled)
 282:      {
 283:        g.setColor(Color.DARK_GRAY);
 284:        g.fillPolygon(triangle);
 285:        g.drawPolygon(triangle);
 286:      }
 287:     else
 288:      {
 289:        g.setColor(Color.GRAY);
 290:        g.fillPolygon(triangle);
 291:        g.drawPolygon(triangle);
 292:        g.setColor(Color.WHITE);
 293:        g.drawLine(baseX1 + 1, baseY + 1, baseX2 + 1, baseY + 1);
 294:      }
 295:   }
 296:   
 297:   /**
 298:    * Paints an downward-pointing triangle.  This method is called by the 
 299:    * {@link #paintTriangle(Graphics, int, int, int, int, boolean)} method.
 300:    * 
 301:    * @param g  the graphics device.
 302:    * @param x  the x-coordinate for the anchor point.
 303:    * @param y  the y-coordinate for the anchor point.
 304:    * @param size  the arrow size (depth).
 305:    * @param isEnabled  if <code>true</code> the arrow is drawn in the enabled
 306:    *                   state, otherwise it is drawn in the disabled state.
 307:    */
 308:   private void paintTriangleSouth(Graphics g, int x, int y, int size, 
 309:           boolean isEnabled)
 310:   {
 311:     int tipX = x + (size - 2) / 2;
 312:     int tipY = y + (size - 1);
 313:     int baseX1 = tipX - (size - 1);
 314:     int baseX2 = tipX + (size - 1);
 315:     int baseY = y;
 316:     Polygon triangle = new Polygon();
 317:     triangle.addPoint(tipX, tipY);
 318:     triangle.addPoint(baseX1, baseY);
 319:     triangle.addPoint(baseX2, baseY);
 320:     if (isEnabled)
 321:      {
 322:        g.setColor(Color.DARK_GRAY);
 323:        g.fillPolygon(triangle);
 324:        g.drawPolygon(triangle);
 325:      }
 326:     else
 327:      {
 328:        g.setColor(Color.GRAY);
 329:        g.fillPolygon(triangle);
 330:        g.drawPolygon(triangle);
 331:        g.setColor(Color.WHITE);
 332:        g.drawLine(tipX + 1, tipY, baseX2, baseY + 1);
 333:        g.drawLine(tipX + 1, tipY + 1, baseX2 + 1, baseY + 1);
 334:      }
 335:   }
 336:   
 337:   /**
 338:    * Paints a right-pointing triangle.  This method is called by the 
 339:    * {@link #paintTriangle(Graphics, int, int, int, int, boolean)} method.
 340:    * 
 341:    * @param g  the graphics device.
 342:    * @param x  the x-coordinate for the anchor point.
 343:    * @param y  the y-coordinate for the anchor point.
 344:    * @param size  the arrow size (depth).
 345:    * @param isEnabled  if <code>true</code> the arrow is drawn in the enabled
 346:    *                   state, otherwise it is drawn in the disabled state.
 347:    */
 348:   private void paintTriangleEast(Graphics g, int x, int y, int size, 
 349:           boolean isEnabled)
 350:   {
 351:     int tipX = x + (size - 1);
 352:     int tipY = y + (size - 2) / 2;
 353:     int baseX = x;
 354:     int baseY1 = tipY - (size - 1);
 355:     int baseY2 = tipY + (size - 1);
 356:     
 357:     Polygon triangle = new Polygon();
 358:     triangle.addPoint(tipX, tipY);
 359:     triangle.addPoint(baseX, baseY1);
 360:     triangle.addPoint(baseX, baseY2);
 361:     if (isEnabled)
 362:      {
 363:        g.setColor(Color.DARK_GRAY);
 364:        g.fillPolygon(triangle);
 365:        g.drawPolygon(triangle);
 366:      }
 367:     else
 368:      {
 369:        g.setColor(Color.GRAY);
 370:        g.fillPolygon(triangle);
 371:        g.drawPolygon(triangle);
 372:        g.setColor(Color.WHITE);
 373:        g.drawLine(baseX + 1, baseY2, tipX, tipY + 1);
 374:        g.drawLine(baseX + 1, baseY2 + 1, tipX + 1, tipY + 1);
 375:      }
 376:   }
 377:   
 378:   /**
 379:    * Paints a left-pointing triangle.  This method is called by the 
 380:    * {@link #paintTriangle(Graphics, int, int, int, int, boolean)} method.
 381:    * 
 382:    * @param g  the graphics device.
 383:    * @param x  the x-coordinate for the anchor point.
 384:    * @param y  the y-coordinate for the anchor point.
 385:    * @param size  the arrow size (depth).
 386:    * @param isEnabled  if <code>true</code> the arrow is drawn in the enabled
 387:    *                   state, otherwise it is drawn in the disabled state.
 388:    */
 389:   private void paintTriangleWest(Graphics g, int x, int y, int size, 
 390:           boolean isEnabled)
 391:   {
 392:     int tipX = x;
 393:     int tipY = y + (size - 2) / 2;
 394:     int baseX = x + (size - 1);
 395:     int baseY1 = tipY - (size - 1);
 396:     int baseY2 = tipY + (size - 1);
 397:     
 398:     Polygon triangle = new Polygon();
 399:     triangle.addPoint(tipX, tipY);
 400:     triangle.addPoint(baseX, baseY1);
 401:     triangle.addPoint(baseX, baseY2);
 402:     if (isEnabled)
 403:      {
 404:        g.setColor(Color.DARK_GRAY);
 405:        g.fillPolygon(triangle);
 406:        g.drawPolygon(triangle);
 407:      }
 408:     else
 409:      {
 410:        g.setColor(Color.GRAY);
 411:        g.fillPolygon(triangle);
 412:        g.drawPolygon(triangle);
 413:        g.setColor(Color.WHITE);
 414:        g.drawLine(baseX + 1, baseY1 + 1, baseX + 1, baseY2 + 1);
 415:      }
 416:   }
 417:   
 418: }